Mars rock ‘surprise’ scientists

WHEN SCIENTISTS selected a rock to test the Mars rover Curiosity’s laser, they expected it to contain the same minerals as rocks found elsewhere on the Red Planet, but learned instead it was more similar to a rock found on Earth.

The rock was chemically more akin to an unusual type of rock found on oceanic islands like Hawaii and St Helena, as well as in continental rift zones like the Rio Grande, which extends from Colorado to Chihuahua, Mexico.

‘‘It was a bit of a surprise, what we found with this rock,’’ Curiosity scientist Ralf Gellert of the University of Guelph in Ontario, Canada, said on Friday.

‘‘It’s igneous,’’ Gellert said, referring to rock formed from molten material. ‘‘But it seems to be a new kind of rock type that we encountered on Mars.’’

Curiosity arrived on Mars two months ago to learn if the most Earth-like planet in the solar system was suitable for microbial life.

Last month, Curiosity’s laser was used to zap the football-sized rock and the rover analysed the pulverised material to determine its chemical composition.

Scientists found the rock lacks magnesium and iron – elements found in igneous rock examined by previous Mars rovers Spirit and Opportunity.

Geologist Edward Stolper, with the California Institute of Technology in Pasadena, said it takes very particular conditions on Earth to produce this type of magma.

The rover meanwhile has moved on to testing and cleaning of its soil scoop. Eventually, scientists want to funnel soil samples to Curiosity’s onboard laboratory for more extensive chemical analysis.

The rover is part way to its first science target, an area known as Glenelg, which has three different types of rock intersecting.

Curiosity is on Mars for year astrobiology mission.

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